1. Field of Use
The present invention is both a device and a method for verifying a subject's identity while using a medical device or undergoing a medical diagnostic or therapeutic procedure, particularly at home or at a remote location.
2. Technology Review
Nearly one in seven people in the United States suffer from some type of chronic sleep disorder, and only 50% of people are estimated to get the recommended seven to eight hours of sleep each night. It is further estimated that sleep deprivation and its associated medical and social costs (loss of productivity, industrial accidents, etc.) exceed $150 billion per year. Excessive sleepiness can deteriorate the quality of life and is a major cause of morbidity and mortality due to its role in industrial and transportation accidents. Sleepiness further has undesirable effects on motor vehicle operation, employment, higher earning and job promotion opportunities, education, recreation, and personal life.
Primary sleep disorders affect approximately 50 million Americans of all ages and include narcolepsy, restless legs/periodic leg movement, insomnia, and most commonly, obstructive sleep apnea (OSA). OSA's prevalence in society is comparable with diabetes, asthma, and the lifetime risk of colon cancer. OSA is grossly under diagnosed with an estimated 80-90% of persons afflicted having not received a clinical diagnosis. Secondary sleep disorders include loss of sleep due to pain associated with chronic infections, neurological/psychiatric disorders, or alcohol/substance abuse disorders.
Sleeping disorders are currently diagnosed by two general methods. Subjective methods, such as the Epworth and Standford Sleepiness Scale, generally involve questionnaires that require patients to answer a series of qualitative questions regarding their sleepiness during the day. With these subjective methods, however, it is found that the patients usually underestimate their level of sleepiness or they deliberately falsify their responses because of their concern regarding punitive action or as an effort to obtain restricted stimulant medication.
The second group of methods uses a combination of sensors and various physiological measurements to examine a subject's sleep health. An example of such an approach is the use of all-night polysomnography (PSG) to evaluate a subject's sleep architecture (e.g., obtaining respiratory disturbance index to diagnose sleep apnea). Sleep testing in this manner typically requires patients to spend the night in a sleep laboratory connected to multiple sensors while they attempt to sleep. Because it is conducted in a laboratory setting, sleep testing cannot provide information about a patient's regular sleeping environment, such as noise, light, or allergens. Sleep testing performed in a laboratory setting can also be difficult to conduct because of a patient's travel concerns or anxiety related to sleeping away from home. Many patients also exhibit a “first night effect” related to a change in sleeping environment. The first night effect often requires a second night in the sleep laboratory to obtain accurate results. Therefore, the first night effect can easily double the cost of conducting a sleep test in a sleep laboratory. Further, these same problems and concerns are equally applicable to sleep therapeutic procedures conducted in a sleep laboratory.
To address the difficulties of conducting sleep testing and therapy in a sleep laboratory, various methods and devices have been developed to perform remote sleep testing and/or therapy from a subject's regular sleeping location. Currently, methods and devices exist which allow remote sleep testing and therapy to be performed using either a remotely attended study or a remote unattended study. In a remotely attended sleep test or therapeutic procedure, data from various sensors is transmitted from the study site to a remote site for analysis in real-time or near real-time. Data transmitted not only includes sleep sensor measurements, but can also include audio and video data, allowing a remote attendant to visually and/or audibly monitor a sleep study in addition to monitoring standard physiological parameters. In unattended remote sleep tests or therapeutic procedures, data from various sleep sensors is simply stored during the sleep test and analyzed by a medical professional at a later time.
The use of remote sleep testing and therapy has many advantages, including alleviation of first night effect, and reduction of cost and inconvenience associated with a subject's being required to travel to a sleep laboratory to undergo these procedures. For these reasons and others, remote sleep testing and therapy has grown significantly in recent times and is likely to continue to increase in prevalence as it becomes more reliable and as understanding of the importance of sleep health continues to increase.
One area of concern associated with the increasing use of unattended remote sleep studies is that of ensuring that the subject for whom a sleep study was intended, is the subject from whom sleep data was in fact collected. Various reasons exist for a subject to falsify sleep test data by having another individual undergo sleep testing in his or her place. Among the most compelling reasons are fear of lifestyle change, fear of possible punitive action and fear that one's employment or means of support may be affected by a positive diagnosis for a sleep disorder. The temptation to falsify sleep test results is of special concern among individuals performing sleep-critical jobs such as over-the-road truck drivers, airline pilots and others similarly employed. Not only are there strong reasons for these individuals to falsify sleep test results because of possible effects on job stability, but the danger posed both to themselves and others such as airline passengers and other drivers is significant.
One method of addressing this concern is to incorporate a subject identification process into the sleep testing procedure. Such a step would serve to ensure that sleep test data is in fact collected from the individual for whom the sleep test was intended. Currently, none of the methods or devices used for unattended remote sleep testing and therapy provide means for verification of patient identity during a sleep diagnostic or therapeutic procedure. Further, none of the methods or devices presently used for sleep testing and sleep therapy performed in a sleep laboratory or performed using remote attendance provide means for simple, secure, biometric verification of subject identity.
It is therefore an object of the present invention to provide a method and device for conducting biometric verification of subject identity as part of unattended remote sleep testing and sleep therapy procedures. It is another object of the present invention to provide a method or device for conducting biometric verification of subject identity as part of sleep testing and sleep therapy procedures conducted in a sleep laboratory as well as sleep testing and sleep therapy procedures which are remotely attended. It is still another object of the present invention to provide a method or device by which biometric identification of a sleep test subject or sleep therapy subject can be performed using a portable sleep diagnostic and/or therapeutic system while the subject sleeps. It is another object of the present invention to provide a method or device for securely handling biometric data in compliance with HIPAA and HCFA standards. It is another object of the present invention to provide a method or device for coordinating the step of biometric verification of a subject's identity with various physical or physiological parameters measured from the subject. It is still another object of the present invention to provide a method or device for coordinating biometric verification of subject identity with sleep onset during sleep testing. Still another object of the present invention is to provide correlation between biometric verification of subject identity and heart rate measured using both ECG and pulse oximetry to ensure that a subject for whom a sleep test was intended is the subject from whom test measurements were acquired.